Method of using an anti-soiling agent composition

Abstract

[Object] To provide an anti-soiling agent compound that can sufficiently prevents adhesion of pitch to a dry part region. [Solution] The present invention provides an anti-soiling agent composition is provided with: a low molecular polysiloxane compound represented by the following formula (1); and a high molecular polysiloxane compound represented by the following formula (2), and characterized in that the number of modified groups per low molecular polysiloxane compound is in a range from 0.1 to 3, the number of modified groups per high molecular polysiloxane compound is in a range from 1.0 to 10, and the number m of repeating polysiloxane units in the low molecular polysiloxane compound and the number n of repeating polysiloxane units in the high molecular polysiloxane compound have the following relationship: 2 m≦n, [in formula (1), substituent R 1 represents a methyl group or a modified group, with the repeating number m being set to an integer from 20 to 200], and [in formula (2), substituent R 2 represents a methyl group or a modified group, with the repeating number n representing an integer].

The invention claimed is: 
     
       1. A method of using an anti-soiling agent composition for preventing pitch contamination in a dry part of a paper-making process, the method comprising:
 applying the anti-soiling agent composition to cylinders of the dry part for use therein, wherein the anti-soiling agent composition comprises: 
 a low molecular polysiloxane compound for dispersing pitch, represented by the following formula (1); and 
 a high molecular polysiloxane compound for use in forming a coat film on the dry part, represented by the following formula (2), 
 wherein the low molecular polysiloxane compound has a kinematic viscosity at 25° C. in a range from 10 to 300 mm 2 /s, while the high molecular polysiloxane compound has a kinematic viscosity at 25° C. in a range from 40 to 90000 mm 2 /s, 
 wherein the modified group in the low molecular polysiloxane compound is an amino-modified group or a polyether-modified group and the modified group in the high molecular polysiloxane compound is an amino-modified group or a polyether-modified group, 
 wherein the number of modified groups per low molecular polysiloxane compound is in a range from 0.1 to 2.0 and the number of modified groups per high molecular polysiloxane compound is in a range from 1.0 to 6.0, and the number m of repeating polysiloxane units in the low molecular polysiloxane compound and the number n of repeating polysiloxane units in the high molecular polysiloxane compound have the following relationship: 2 m≦n, 
 wherein the high molecular polysiloxane compound has a compounding ratio in a range from 1 to 20% by weight, the low molecular polysiloxane compound has a compounding ratio in a range from 5 to 20% by weight, and the low molecular polysiloxane compound has a compounding ratio in a range from 0.1 to 10 parts by weight relative to 1 part by weight of the high molecular polysiloxane compound, 
 wherein the anti-soiling agent composition is sprayed to the cylinders by using a spraying nozzle so that the sprayed amount thereof per unit area of paper passing therethrough is set in a range from 10 μg/m 2  to 1000 μg/m 2  as a solid component of the polysiloxane compound, 
 
       
         
           
           
               
               
           
         
         wherein substituent R 1  represents a methyl group or a modified group, with the repeating number m being set to an integer from 20 to 50, and 
       
       
         
           
           
               
               
           
         
         wherein substituent R 2  represents a methyl group or a modified group, with the repeating number n representing an integer of 280 or more and less than 1430. 
       
     
     
       2. The method according to  claim 1 , wherein the modified group in the low molecular polysiloxane compound is represented by the following formula (3),
   —R 3 —NH—R 4 —NH 2   (3)
 
 wherein a substituent R 3  represents a propylene group and a substituent R 4  represents an ethylene group. 
 
     
     
       3. The method according to  claim 1 , wherein the modified group in the low molecular polysiloxane compound is represented by the following formula (4),
   —R 5 —NH 2   (4)
 
 
       wherein a substituent R 5  represents an alkylene group having 1 to 6 carbon atoms. 
     
     
       4. The method according to  claim 1 , wherein the modified group in the high molecular polysiloxane compound is represented by the following formula (5),
   —R 6 —NH—R 7 —NH 2   (5)
 
 wherein a substituent R 6  represents a propylene group and a substituent R 7  represents an ethylene group independently. 
 
     
     
       5. The method according to  claim 1 , wherein the modified group in the high molecular polysiloxane compound is represented by the following formula (6),
   —R 8 —NH 2   (6)
 
 
       wherein a substituent R 8  represents an alkylene group having 1 to 6 carbon atoms. 
     
     
       6. The method according to  claim 1 , wherein the anti-soiling agent composition further comprises an emulsifier for emulsifying the low molecular polysiloxane compound and the high molecular polysiloxane compound. 
     
     
       7. The method according to  claim 6 , wherein the emulsifier has a compounding ratio in a range from 0.05 to 0.4 parts by weight relative to 1 part by weight of a mixture of the high molecular polysiloxane compound and the low molecular polysiloxane compound.